package translations;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.util.HashMap;
import java.util.Map;


public class MessagePoolFactory<T> {
    private Class<T> messageModuleClass;


    private Map<Method, Map<String, String>> translations = new HashMap<Method, Map<String, String>>();

    public MessagePoolFactory(Class<T> messagePoolInterface) {
        if (!messagePoolInterface.isInterface()){
            throw new IllegalArgumentException("MessagePoolInterface must be an interface.");
        }
        this.messageModuleClass = messagePoolInterface;

        for (Method method : messagePoolInterface.getDeclaredMethods()){
            Translations translationsAnnotation = method.getAnnotation(Translations.class);
            if (translationsAnnotation == null)
                continue;
            Map<String, String> map = new HashMap<String, String>();
            for (Entry entry : translationsAnnotation.entries()){
                map.put(entry.key(), entry.value());
            }
            translations.put(method, map);
        }


    }

    public T getLanguageSource(final String language) {
        return (T) Proxy.newProxyInstance(messageModuleClass.getClassLoader(), new Class[]{messageModuleClass}, new InvocationHandler() {
            public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
                return String.format(translations.get(method).get(language), args);
            }
        });
    }

}